Pitch-Based Earcons: An Auditory Display for Patient Monitoring

Clinicians who have a continual awareness of a patient’s vital sign levels are more likely to detect and respond to early indicators of the patient’s physiological deterioration. Auditory displays are informative patient monitoring tools that can convey vital sign information through short abstract tones, known as earcons. In an earlier study, Janata and Edwards (2013) tested participants’ accuracy at identifying changes in vital sign levels using earcons in which timbre represented oxygen saturation (SpO2) and tremolo represented heart rate (HR) levels. However, the earcons were only moderately effective at supporting the monitoring of SpO2 levels. In the present study, we tested participants’ accuracy at identifying vital sign levels using a novel set of pitch-based earcons (pearcons). The pearcons used pitch and tremolo to represent SpO2 and HR levels respectively. It was hypothesized that if pitch is more discernible or more integral with tremolo than timbre is, then participants who listened to pearcons would identify the vital sign levels more accurately than participants who listened to earcons. Results showed that participants who listened to the pearcons were more accurate at identifying vital sign levels than participants who listened to the earcons. Additionally, SpO2 identification accuracy was lower when HR level changed at the same time, than when HR level was constant. However, between the pearcons and the earcons condition there was no difference in each vital sign identification accuracy change from trials where the other vital sign was constant, to trials where the other vital sign changed. This study showed preliminary evidence that pearcons are more effective than earcons for patient monitoring, possibly because pitch is fundamentally more discernible than timbre. Future studies should examine the effectiveness of pearcons in a more clinically representative context